Soft robotic retractors

ABSTRACT

Exemplary embodiments describe soft robotic actuators for medical use, such as during surgeries and other medical procedures. According to one embodiment, a soft robotic incision retractor is provided. According to another embodiment, a soft robotic body tissue retractor is provided. The incision retractor and body tissue refractor may be used together, for example by using the incision retractor to hold open an incision while the body tissue retractor manipulates biological matter or an object accessible through the incision. Described embodiments offer the ability to conform to a given space, reduced risk of damage to surrounding structures as compared to traditional retractors, the ability to deliver varying amounts of force, the ability to be made from medically safe materials, and the potential for re-use or disposability.

RELATED APPLICATIONS

The present application claims priority to U.S. Patent Applications Ser.No. 62/079,302, filed on Nov. 13, 2014. The contents of theaforementioned applications are incorporated herein by reference.

FIELD OF THE DISCLOSURE

The disclosure relates generally to the field of robotics andparticularly to medical retractors employing soft robotic actuators.

BACKGROUND

Robotics are used in many industries, such as manufacturing, industrialapplications, medical applications, and the like. Soft robotics is adeveloping area of robotics that provides soft, conformal, and adaptivegraspers and actuators to enable robots to interact with objects in asimilar manner to a human. In particular, such robots are able tomanipulate objects in the same manner as a human hand.

Soft robotics have been employed in connection with robotic systems forgrasping objects on an assembly line or in a warehouse. For example, ifa part is in a bin, on a shelf, a moving belt, or being moved from ashelf to a belt, an end effector may adapt to picking up the object fromvarious directions, such as a “side pick” or a “top down pick.” Thissame grasper may also adapt to varying objects in each task, just as thehuman hand can.

SUMMARY

Exemplary embodiments apply the concept of soft robotic actuators to themedical field, and more specifically provide soft robotic retractors foruse during surgeries and other medical procedures. Soft roboticactuators have a number of advantages, including the ability to conformto a given space, reduced risk of damage to an object being manipulatedor to surrounding structures as compared to traditional retractors, theability to deliver varying amounts of force, the ability to be made frommedically safe materials, and the potential for re-use or disposability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1D depict exemplary incision retractors employing soft roboticactuators.

FIGS. 2A-2D depict exemplary body lumen retractors employing softrobotic actuators.

FIGS. 3A-3C depict an example of the exemplary incision retractor andthe exemplary body lumen retractor in use.

FIGS. 4A-4E are various perspective views showing an exemplary incisionretractor in more detail.

FIGS. 5A-5E are various perspective views showing an exemplary bodylumen retractor in more detail.

FIG. 6 is a flowchart depicting an exemplary process for using theincision retractor and body lumen retractor.

FIGS. 7A-7H depict an exemplary incision retractor and an exemplary bodylumen retractor performing the steps described in FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. The invention, however, may be embodied inmany different forms and should not be construed as being limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. In thedrawings, like numbers refer to like elements throughout.

Exemplary embodiments provide soft robotic actuators for medical use,such as during surgeries and other medical procedures. According to oneembodiment, a soft robotic incision retractor is provided. According toanother embodiment, a soft robotic body tissue retractor is provided.The incision retractor and body tissue retractor may be used together,for example by using the incision retractor to hold open an incisionwhile the body tissue retractor manipulates biological matter or anobject accessible through the incision. Described embodiments offer theability to conform to a given space, reduced risk of damage tosurrounding structures as compared to traditional retractors, theability to delivery varying amounts of force, the ability to be madefrom medically safe materials, and the potential for re-use ordisposability.

A brief overview of soft robotic actuators is now provided.

Soft Robotic Actuators

Conventional robotic grippers or actuators may be expensive andincapable of operating in certain environments where the uncertainty andvariety in the weight, size and shape of the object being handled hasprevented automated solutions from working in the past. The presentapplication describes applications of novel soft robotic actuators thatare adaptive, inexpensive, lightweight, customizable, and simple to use.

Soft robotic actuators may be formed of elastomeric materials, such asrubber. They may be created, for example, by molding one or more piecesof the elastomeric material into a desired shape. Soft robotic actuatorsmay include a hollow interior that can be filled with a fluid, such asair, water, or saline to inflate and actuate the actuator. Uponactuation, the shape or profile of the actuator changes. In the case ofan accordion-style actuator (described in more detail below), actuationmay cause the actuator to curve or straighten into a predeterminedtarget shape. One or more intermediate target shapes between a fullyunactuated shape and a fully actuated shape may be achieved by partiallyinflating the actuator.

Actuation may also allow the actuator to exert a force on an object,such as an object being grasped or pushed. However, unlike traditionalhard robotic actuators, soft actuators maintain adaptive properties whenactuated such that the soft actuator can partially or fully conform tothe shape of the object being grasped. Moreover, the amount of forceapplied can be spread out over a larger surface area in a controlledmanner. In this way, soft robotic actuators can grip objects withoutdamaging them.

Moreover, soft robotic actuators allow for new types of motions orcombinations of motions (including bending, twisting, extending, andcontracting) that can be difficult or impossible to achieve withtraditional hard robotic actuators.

Exemplary embodiments leverage the advantages of soft robotic actuatorsto provide retractors suitable for use in medical applications, asdiscussed below.

Applications

In the medical context, soft robotic actuators have a number ofadvantages. Soft robotic actuators have the ability to conform to agiven space, which means that they can apply a force to tissue or bodylumens that may be irregularly sized or difficult to reach. Because softrobotic actuators are conformal and adaptive, and because they can bemade from medically safe elastomeric materials, there is a reduced riskof damage to surrounding structures using a soft robotic actuator ascompared to traditional retractors. Moreover, soft robotic actuators candeliver varying amounts of force, allowing the retractors to adapt tochanging requirements. Still further, because of the wide variety ofmaterials that can be used to make a soft robotic actuator, actuatorscan be manufactured with the potential for reuse, partial reuse, ordisposability, depending on the needs of the user. Still further,because the actuators can change size, they can be passed through smallopenings (as might be useful, for example, in laparoscopic surgery).After passing through the opening, the actuator may be expanded in sizeon the far side of the opening to place the actuator in a state in whichit can retract or manipulate the target.

Examples of procedures in which soft robotic actuators may beparticularly useful include, but are not limited to, open soft tissuemanagement, open surgical adhesiolysis, open surgical appendectomy, opensurgical gastric bypass, open surgical cholecystectomy, open surgicalesophagogastric fundoplasty, open surgical herniorrhaphy, partialcolectomy, complete colectomy, sigmoidectomy, conventionalhemorrhoidectomy, open surgical biopsy, intestine transplant, kidneytransplant, liver transplant, partial nephrectomy, radical nephrectomy,splenectomy, partial lung resection, lobectomy, open lung biopsy,thoracoscopy procedures, and surgical trauma.

Exemplary soft robotic retractors suitable for use with these (andother) types of procedures are now described.

Exemplary Embodiments

Two types of soft robotic actuators are discussed herein. Incisionrefractors are designed to be inserted into a location in a body, suchas at an incision location or at a location of a wound, and to supportthe edges of the incision or wound in order to provide a defined workingspace at the location. Body tissue refractors are designed to beinserted into a working space in a body in order to manipulatebiological matter or an object in the working space in order to providebetter visual or physical access to a target tissue or organ. Forexample, a bowel retractor may be used to manipulate a patient'sintestines, to move the intestines out of the way during a surgicalprocedure.

An exemplary incision retractor is depicted in FIGS. 1A-1D. Morespecifically, FIG. 1A depicts a side view of a portion of the incisionrefractor that is deployed in an incision. FIG. 1B depicts the portionfrom FIG. 1A from the top. FIG. 1C depicts a side view of a portion ofthe incision retractor that is maintained outside of the incision and ismanipulated by a user. FIG. 1D depicts an alternative embodiment for theexternal portion depicted in FIG. 1C.

Although the following description describes these devices as “incision”retractors, one of ordinary skill in the art will recognize that thepresent invention is not so limited. In addition to providing retractioncapabilities at areas of incisions, the exemplary incision retractorsdescribed herein can be used to provide retraction capabilities at anysuitable location (e.g., intra-abdominal organ retraction).

The incision retractor generally includes a soft robotic actuator 100,which is inflatable with an inflation fluid. The inflation fluid may beprovided via an inflation device 120 through flexible tubing 118.

In general, an incision retractor should provide safe, reliable, andmaximal physical and visual access to subcutaneous anatomy via an openincision of minimal size. The exemplary incision retractor can bedeployed by inflating the soft robotic actuator 100; prior to orfollowing deployment, the soft robotic actuator 100 may be in anuninflated state. When inflated, the actuator 100 has a substantially“C” or partial oval shape; prior to inflation or following deflation,the actuator 100 takes on a relatively flat shape and can be folded, ifdesired. This allows the retractor to maximize physical and visualaccess when deployed, while having a minimal profile during insertioninto an incision.

In the inflated state, the actuator 100 curves around a central axis, asshown in FIG. 1A. For ease of discussion, several directions are definedherein. An axial direction passes through the central axis, as shown inFIG. 1B. A radial direction extends in a direction perpendicular to theaxial direction, in the direction of the radius of the circle formed bythe inflated actuator 100. A circumferential direction extends along acircumference of the inflated actuator 100.

In the inflated state, the actuator 100 may exert between 0.1 and 5pounds of force pounds of force in the radial direction along thecircumferential edge of the actuator 100. In some embodiments, theactuator exerts 1 to 3 pounds of force. In one embodiment, the actuatorexerts about 1.5 pounds of force.

The amount of force that a given retractor is able to exert may bevaried in a number of ways. For example, a larger actuator 100 willdeliver more force at the same degree of inflation pressure as comparedto a smaller actuator 100. By adding reinforcements to the actuator 100,such as fiber reinforcements, more force can be delivered in the sameform factor by being able to operate at a higher pressure. Similarly, bydesigning the actuator 100 with thin sheets of plastic or relativelystiff elastomers, more force could be delivered with the same sizedactuator by utilizing a higher inflation pressure.

The construction of the incision retractor provides sufficient staticand dynamic strength to repeatedly retract soft tissues while behavingreliably and predictably under varying external loads (e.g., therefractor does not shift or dislodge under stress). Similarly, theretractor behaves reliably when physically manipulated in the inflatedstate (without undesirably shifting or dislodging during themanipulation). These benefits occur, in part, because the soft roboticactuator remains relatively conformal when inflated, due to thematerials used (e.g., the materials that make up the body of theactuator and the fluid used to inflate the actuator) and the generalconstruction of the device. Because the device is relatively conformal,it takes on the shape of the area in which it is deployed, to a certaindegree, and hence can remain relatively stable.

The actuator 100 may be made of one or more elastomeric materials thatallow for a relatively soft or conformal construction. The elastomericmaterials may be selected from a group of biocompatible or otherwisemedically safe, FDA-approved materials. The actuator 100 may incorporatepolymers that have drug eluting capabilities or antimicrobial coatings.The actuator 100 may be manufactured in a Good Manufacturing Process(“GMP”)-capable facility.

The actuator 100 may include a base 102 that is substantially flat. Wheninflated, the area inside of the base 102 (i.e., the area radiallyinterior to the base 102) forms the working area through whichsubcutaneous matter can be manipulated. Because the base 102 issubstantially flat whereas the top is not (due to the accordionextensions discussed below), the actuator is inclined to bend in aradially outward direction Moreover, making the base 102 substantiallyflat provides a relatively large working area as compared to if the base102 were not flat.

Alternatively, the base 102 may incorporate one or more overmolded slatsor other suitable stiff structures to prevent the base from bowing uponpressurization, which may further increase the available work area. Thebase 102 of a soft actuator can have the tendency to bow away from theneutral bending plane of the actuator during inflation. This bowing ofthe base 102 increases the second moment of area of the actuator's crosssection, thereby increasing the actuator's resistance to bending. Thisbehavior diminishes the function of the actuator 100. This problem canbe mitigated by overmolding rigid elements (e.g. plastics,metals,ceramics, or stiffer elastomers) in to the base 102. This isaccomplished by placing a plurality of rigid elements into the base 102where the long axis of each element is oriented perpendicular to theneutral axis of bending. This orientation allows the rigid elements toprevent bowing of the base 102 in the direction perpendicular to theneutral axis but only minimally impedes bending along the neutral axis.By reducing the tendency of the base 102 to bow outwards, the rigidelements may provide an expanded working area.

The actuator 100 may include one or more accordion extensions 104. Theaccordion extensions 104 allow the actuator 100 to bend or flex wheninflated, and help to define the shape of the actuator 100 when in aninflated state. The accordion extensions 104 include a series of ridges106 and troughs 108. The size of the accordion extensions 104 and theplacement of the ridges 106 and troughs 108 can be varied to obtaindifferent shapes or extension profiles.

Although the exemplary incision retractor of FIGS. 1A-1D is depicted ina “C” or oval shape when deployed, one of ordinary skill in the art willrecognize that the present invention is not so limited. By changing theshape of the body of the actuator 100, or the size, position, orconfiguration of the accordion extensions 104, different sizes, shapes,and configurations may be achieved. Moreover, varying the amount ofinflation fluid provided to the actuator 100 allows the retractor totake on one or more intermediate sizes or shapes between the un-inflatedstate and the inflated state. Thus, an individual actuator 100 can bescalable in size and shape by varying inflation amount, and an incisionretractor can be further scalable in size and shape by replacing oneactuator 100 with another actuator 100 having a different size, shape,or configuration.

The actuator 100 may be repositionable and adjustable intra-operatively.This may enable highly dynamic procedures, such as bowel runs, to beperformed.

The actuator 100 extends from a proximal end 112 to a distal end 110.The proximal end 112 connects to an interface 114. The interface 114allows the actuator 100 to be releasably coupled to other parts of theincision retractor. The interface 114 may be made of a medically safematerial, such as Acrylonitrile-Butadiene-Styrene (“ABS”) or Delrin. Theinterface 114 may be releasably coupled to one or both of the actuator100 and the flexible tubing 118. The interface 114 may have a port forconnecting to the actuator 100. Different interfaces 114 may havedifferent sizes, numbers, or configurations of actuator ports, in orderto accommodate larger or smaller actuators, different numbers ofactuators, or actuators in different configurations.

The actuator 100 may be inflated with an inflation fluid supplied froman inflation device 120 through flexible tubing 118. The interface 114may include or may be attached to a valve 116 for allowing fluid toenter the actuator 100 but preventing the fluid from exiting theactuator (unless the valve is opened). The flexible tubing 118 may alsoor alternatively attach to an inflator valve 124 at the inflation device120 for regulating the supply of inflation fluid at the location of theinflation device 120.

The flexible tubing 118 may also include an actuator connectioninterface 122 for releasably connecting to the interface 114 at one endand the inflation device 120 at the other end. By separating the twoparts of the actuator connection interface 122, different inflationdevices 120 may be connected to different interfaces 114 and/oractuators 100.

The inflation fluid may be, for example, air or saline. In the case ofair, the inflation device 120 may include a hand-operated bulb,bellows,catheter balloon inflator, or syringe for supplying ambient air. In thecase of saline, the inflation device 120 may include a syringe or otherappropriate fluid delivery system. Alternatively or in addition, theinflation device 120 may include a compressor or pump for supplying theinflation fluid.

In some applications, saline may be a preferred inflation fluid. Forexample, in certain applications saline may be superior to air due tothe fact that, in the unlikely event that the actuator 100 shouldrupture or develop a leak, the liquid saline will depressurize theactuator 100 with minimal volume expansion thereby causing less damageto the patient. In contrast, if an actuator 100 containing compressedair ruptures, the air will undergo a significant volume expansion thatcould injure a patient. In addition, this event could leave air pocketsin the patient, which could be dangerous (e.g., if the air pockets werelocated in the patient's vascular system).

For example, FIG. 1D depicts an alternative inflation device 120. Theinflation device 120 includes a fluid supply 126 for supplying aninflation fluid. For example, the fluid supply 126 may be a reservoirfor storing compressed air or saline, a cartridge storing pressurized orliquefied gas (such as carbon dioxide), or may be a vent for supplyingambient air to the flexible tubing 118.

The inflation device 120 further includes a fluid delivery device 128,such as a pump or compressor, for supplying inflation fluid from thefluid supply 126 to the actuator 100 through the flexible tubing 118.The fluid delivery device 128 may be capable of supplying fluid to theactuator 100 or withdrawing the fluid from the actuator 100. The fluiddelivery device 128 may be powered by electricity. To supply theelectricity, the inflation device 120 may include a power supply 130,such as a battery or an interface to an electrical outlet.

The power supply 130 may also supply power to a control device 132. Thecontrol device 132 may allow a user to control the inflation ordeflation of the actuator, e.g. through one or more actuation buttons134 (or alternative devices, such as a switch). The control device 132may include a controller 136 for sending a control signal to the fluiddelivery device 128 to cause the fluid delivery device 128 to supplyinflation fluid to, or withdraw inflation fluid from, the actuator 100.

Different geographies or business needs may dictate differentrequirements for the incision retractor. For example, depending on theneeds of the user, the incision retractor may be designed to bedisposable, reusable, or partially disposable and partially reusable.

For example, the incision refractor as a whole may be disposable. In adisposable configuration, each component of the incision retractor isdesigned to be a sterile, single-use component. The inflation device 120may be a hand-operated inflator bulb or bellows. The inflation device120 may provide a working fluid of air or saline as an inflation fluid.

In this configuration, the incision retractor does not require a largeup-front investment of capital, and is relatively easy to use. Moreover,no maintenance is required, as the incision retractor can simply bedisposed of after use.

Alternatively, the incision retractor as a whole may be reusable. Inthis configuration, the components of the retractor (particularly theactuator 100) may be constructed of relatively high-grade materials thatare compatible with cleaning in an autoclave. The inflation device 120may be hand-operated (e.g., an inflation bulb or bellows), or may beelectronic (with or without an off-board control device). The inflationdevice 120 may provide a working fluid of air or saline as an inflationfluid.

In this configuration, although a larger up-front cost may be required,longer-term costs over time may be smaller due to the fact that incisionretractors do not need to be replaced after each operation. Moreover,because each retractor is designed for multiple uses, the retractors canbe provided with more functionality and durability.

Alternatively, portions of the incision retractor may be designed to bedisposable, while other portions are reusable. For example, theinflation device 120 and/or control device 136 may be reusable, whilethe actuator 100 may be single-use and disposable. The inflation device120 may provide a working fluid of saline as an inflation fluid.

In some applications, surgeons may require that sufficient tissueperfusion occur at the margins of the incision. Therefore, in order tostimulate tissue perfusion, in some embodiments the refractor may beconfigured to vibrate or pulse intermittently. For example, the actuator100 may be provided with a small vibration device powered locally orfrom the inflation device 120. In these embodiments, the actuator 100should be sufficiently sturdy so as to maintain the amount of retractionand the shape of the retracted incision. In some embodiments vibrationmay be achieved with a vibratory motor, and pulsation may be achieved bycyclically modulating pressure (e.g., automatically through a controldevice or manually through a hand-held inflation device).

The incision retractor may be used in conjunction with a body tissueretractor. Exemplary body tissue retractors are depicted in FIGS. 2A-2D.

The body tissue retractor may be used to manipulate, retract, orsequester body tissue, organs, or objects while reducing the potentialfor injury, unintended reduction of perfusion, or tissue puncture. Thisallows surgeons to maximize visual and physical access to targetsubcutaneous anatomy via an open incision of minimal size. The bodytissue retractor is therefore capable of exerting sufficient static anddynamic strength to repeatedly retract soft and sensitive organs.

The body tissue retractor may be operated by hand in some embodiments,but the present invention is not so limited. For example, some or all ofthe body tissue retractor may be mounted at the end of a robotic arm forthe purpose of performing robotic surgery.

Moreover, although the body tissue retractor may be used in conjunctionwith the above-described incision retractor, the body tissue retractormay additionally or alternatively be used in conjunction with otherdevices. In one embodiment, the body tissue retractor may be fed througha trocar for the purpose of performing laparoscopic surgery.

Furthermore, due to the relatively compliant nature of the retractor,the retractor is capable of behaving reliably under varying externalloads and when the refractor is physically manipulated in an inflatedstate. In particular, the retractor does not shift or dislodge whenmanipulated or subjected to external stress.

Moreover, the retractor should apply safe pressures to retracted tissue.This allows surgeons to maximize or maintain the health of retractedtissue.

As shown in FIG. 2A, the body tissue retractor includes a handle 200 toallow a user to manipulate the body tissue retractor. The handle may beergonomically designed for a comfortable grip. The handle 200 mayinclude a hand-operated inflation device 202, such as a bulb or bellows.The inflation device 202 may include one or more valves to allow theinflation device 202 to operate as a hand pump (e.g., a sphygmomanometerbulb). The inflation device 202 of the body tissue retractor may be ofsimilar construction to the inflation device 120 of the incisionretractor (including the variations discussed above).

In some embodiments, the body tissue retractor may provide hapticfeedback to a user or to a control device. For example, the inflationdevice 202 may be filled with a predetermined amount of fluid that isconfined or trapped in a system made up of the inflation device 202,tubing inside the shaft 206, and the actuator 100. When a user orcontrol device activates the inflation device 202, some of the fluidexits the inflation device 202 and is directed to the actuator 100. Atsome point, the actuator 100 may make contact with an object, causingthe actuator 100 to deflect. When the actuator 100 deflects, an amountof inflation fluid proportional to the amount of deflection is forcedback out of the actuator 100, into the tubing, and returns to theinflation device 202. This causes an inflation force to be exerted onthe inflation device 202, which allows for an operator or controller tofeel the deflection of the actuator 100 directly through a tactileinteraction with the inflation device thereby providing haptic feedback.This may allow, for example, a surgeon to feel the degree of tissueretraction that is achieved without the need to use an electronicvisualization device, such as a camera, or an expensive haptic roboticfeedback device.

The inflation fluid that exits the actuator 100 in response to thedeflection may also be measured by one or more sensors, such as apressure sensor and/or a flow sensor, that are present in the actuator100, the shaft 206, or the inflation device 202. For example, a flowsensor may measure the flow of the inflation fluid from the actuator 100back into the inflation device. In another embodiment, the inflationdevice 202 may be held in a state where its volume is locked. Asinflation fluid flows back into the inflation device 202, the overallpressure of the system would increase, which may be measured by apressure sensor.

The sensor outputs may be read by a controller (e.g., in digital form)and may serve as an input signal that the controller processes togenerate haptic feedback. The controller may output a feedback signalproportional to the input signal from the sensor outputs, where thefeedback signal causes a haptic device in the handle 200 to generate ahaptic output that can be felt by an operator of the handle 200.Alternatively or in addition, the haptic output feedback signal may notbe proportional to the input signal. For example, if the force deliveredby the retractor approaches a predetermined threshold (e.g.,corresponding to a patient pain threshold or a threshold above whichdamage to the tissue is risked), the output feedback signal may varynon-linearly so that the tactile feedback becomes more intense. This mayserve as a warning of impending danger.

In one embodiment these signals could be used to trigger the action of avibratory motor in the handle 200 in order to provide the user with atactile indication that the actuators 100 are being deflected.

The handle 200 may also include a valve actuator 204, such as a pin, forallowing a user to open or close a valve that sits in a fluid pathbetween the inflation device 202 and an actuator 100. The valve actuator204 may be similar to the interface valve 116 or the inflator valve 124of the incision retractor, discussed above.

The handle 200 may connect to a shaft 206 that extends from the handle200. The shaft 206 allows the body tissue retractor to reach into anarea inside of an incision to manipulate subcutaneous matter.

The shaft 206 also serves as a conduit for routing inflation fluid fromthe inflation device 202 to the actuator 100. To this end, the shaft 206may include a flexible elastomeric material to ease assembly of thedevice. For example, a tube made of rubber or other elastomeric materialmay be inserted into the hollow center of the shaft 206 in the axialdirection. Because the tube is elastomeric, the tube may expand whenpulled in the axial direction, and may return to its original size whenthe pulling force is released. The tube may include an interface at eachend, one for attaching to the inflation device 202 and one for attachingto the actuator 100 or the interface 208. By pulling on the tube, thetube may lengthen so that it extends beyond the ends of the shaft 206,which allows the inflation device 202, the interface 208, and/or theactuator 100 to be easily attached. Releasing the pulling force causesthe tube to retract back into the shaft. The interfaces at each end ofthe tube may be configured to sit flush with the ends of the shaft 206when the tube returns to its unextended state.

The shaft 206 may connect to an interface 208, which may be similar tothe interface 114 of the incision retractor. In particular, theinterface 114 may support the actuator 100 and allow different types orsizes of actuators, different numbers of actuators, or differentconfigurations of actuators to be attached to the body tissue retractor.For example, although FIGS. 2A-2D depict a body tissue retractor havingtwo actuators, other embodiments may include three or more actuators invarious configurations. In one embodiment, an additional actuator may beplaced between the two actuators shown in the Figures, in order tochange the spread angle between the fingers. Alternatively or inaddition, a cable may be provided that is attached to a spring betweenthe fingers. By pulling on the cable, the spread angle between thefingers may be changed. The cable may run from the actuator(s) 100 tothe handle 200 so the operator can change the tension on the cable byhand or with a machine/motor, which then has the effect of spreading theactuator(s) 100.

The actuator(s) 100 attached to the interface 208 may be generallysimilar to the actuators described above in connection with the incisionretractor, but may be sized and configured in order to customize thebody tissue retractor to a particular application (e.g., manipulatingbowel matter).

In the inflated state, the actuator 100 may exert from about 0.1 poundsto 5 pounds of force in the circumferential direction. In someembodiments, the actuator 100 exerts about 0.2 to 2 pounds of force. Theinflation characteristics of an exemplary bowel tissue retractor areshown in FIGS. 2C and 2D.

FIG. 2B depicts an alternative inflation mechanism for inflating theactuator 100. The inflation mechanism is operated by a foot pedal 210,which is operable to send a control signal through a signal line 212 toa control device 214. The control device 214 may be configured similarlyto the inflation device 120 of FIG. 1D, including a fluid delivery line216 for providing an inflation fluid from a fluid supply 126 to thehandle 200, and from there through the shaft 206 to the actuator(s) 100.

It is noted that the alternative inflation mechanism of FIG. 2B couldalso be applied to the incision retractor of FIGS. 1A-1D.

As with the incision retractor, the body tissue retractor may beconfigured to be entirely disposable, entirely reusable, or partiallydisposable and partially reusable. In the disposable configuration, theshaft 206 may be constructed of aluminum, and the interface 208 may bemolded from ABS. The actuator(s) 100 may be constructed of surgicalsilicone, and the inflation fluid may be air.

In the reusable configuration, the shaft 206 may be constructed ofstainless steel, the interface 208 may be molded of Delrin, the actuatormay be made of surgical silicone or thermoplastic polyurethane, and theinflation fluid may be saline. Such a body tissue retractor may bedeployed with an off-board control system to allow for hand and/or footpedal control.

In the partially reusable configuration, the body tissue retractor mayutilize reusable component materials. The end effector may be made up ofan interface 208 made from ABS and disposable actuator(s) 100. Theinflation fluid may be saline, and the system may be connected to anoff-board control system to enable hand and foot pedal control.

An exemplary use of the incision retractor and the body tissue retractoris shown in FIGS. 3A-3C. FIG. 3A depicts an un-inflated incisionretractor in a simulated incision. As shown in FIG. 3A, the un-inflatedincision refractor is generally smaller than the area of the incisionand can be deployed in a relatively flat configuration (e.g., by foldingor bending the actuator 100). As is apparent from FIG. 3A, only arelatively small part of opening created by the incision is accessiblethrough the incision retractor when the actuator is in the un-inflatedstate.

FIG. 3B depicts the incision retractor after the actuator 100 has beeninflated. As shown in FIG. 3B, upon inflation the incision retractortakes on a substantially uniform shape along a length of the actuatorfrom a proximal end to a distal end in a circumferential direction,becoming C-shaped or partially elliptical. As compared to theun-inflated state shown in FIG. 3A, the inflated actuator 100 of FIG. 3Ballows access to a relatively larger part of the opening created by theincision.

It is noted that the actuator 100 becomes elliptical in shape whendeployed in the incision or wound. If the same actuator 100 is inflatedin free space, it may take on a substantially circular shape. Becausethe actuator 100 is configured to take on a substantially circular shapein free space, it exerts an opening force on the non-circular incisionor wound opening when deployed in the incision or wound as it attemptsto take on a substantially circular shape. Because an incision istypically a straight line or a non-circular profile, the incised tissueresists the load applied by the actuator 100 as it attempts to achieve acircular state. As the actuator 100 attempts to push itself into acircular state, a load is applied to the resisting tissue which causesthe incision to open.

Once the incision is opened using the incision retractor, the bodytissue retractor may be inserted into the opening created by theactuator 100, as shown in FIG. 3C. By inflating the actuator(s) of thebody tissue retractor, the actuators may take on a relatively more rigid(though still conformal) shape, allowing for the manipulation of bodytissue, organs, or objects accessible through the incision.

Further views of the incision retractor and the body tissue retractorare provided in FIGS. 4A-5E. FIGS. 4A-4E depict various perspectiveviews of an exemplary incision retractor, while FIGS. 5A-5E depictvarious perspective views of an exemplary body tissue retractor, and inparticular a soft robotic bowel retractor.

FIG. 6 is a flowchart 600 describing an exemplary method for using asoft robotic incision retractor in conjunction with a soft robotic bodytissue retractor. FIGS. 7A-7H illustrate the steps described in FIG. 6.

At step 602, the incision retractor may be placed at a desired location.The incision retractor may be in an initially uninflated state, and maybe folded or bended in order to allow for easier insertion at thedesired location. The location may be, for example, inside of anincision or wound. An example of placing the incision refractor at sucha location is shown in FIG. 7A.

At step 604, the incision retractor inflation device may be actuated. Auser may trigger actuation by actuating an inflation device 120, orpressing an actuation button 134 to send a control signal to a fluiddelivery device 128. The incision retractor's actuator may undergoinflation as a result of actuation. The actuator may enter anintermediate partially inflated state, as shown in FIG. 7B, before itbecomes fully inflated, as shown in FIG. 7C. Depending on theapplication and the needs of the user, the actuator may be left in thepartially inflated state, or may be fully inflated.

At step 606, the tissue retractor valve actuator may be closed. Closingthe tissue retractor valve actuator allows for one-way communication ofthe inflation fluid into the tissue retractor actuator(s), withoutallowing inflation fluid to exit the tissue retractor actuator(s). Forexample, if the tissue retractor valve actuator is a pin, the pin may berotated into a closed position.

At step 608, the tissue retractor may be inserted through the opening inthe incision retractor. The tissue retractor may be in an initiallyuninflated state, as shown in FIG. 7D.

At step 610, the tissue retractor inflation device may be actuated. Auser may trigger actuation by actuating an inflation device 202, orpressing an actuation button 134 or actuation pedal 210 to send acontrol signal to a fluid delivery device 128. The tissue retractor'sactuator(s) may undergo inflation as a result of actuation. The actuatormay enter an intermediate partially inflated state, as shown in FIG. 7E,before it becomes fully inflated, as shown in FIG. 7F. Depending on theapplication and the needs of the user, the actuator may be left in thepartially inflated state, or may be fully inflated.

At step 612, a manipulation may be performed using the actuator(s) ofthe tissue retractor. For example, the tissue retractor may be used tomove subcutaneous material out of the way so that a surgeon can access aphysical space that would otherwise be blocked. FIG. 7G depicts asimulated example of performing a manipulation with the tissueretractor.

At step 614, the tissue retractor valve actuator may be opened. Thisallows the inflation fluid to be evacuated from the tissue retractoractuator(s), causing the actuator(s) to enter an uninflated state.

At step 618, the tissue retractor may be removed from the area of theincision held opened by the incision retractor, as shown in FIG. 7H.

At step 620, the incision retractor may be removed. Step 620 may involveopening one or more valves attached to the incision retractor to allowinflation fluid to escape the actuator of the incision retractor. Whenthe retractor has returned to an uninflated state, the incisionretractor may be removed from the area of the incision. The incision maynow be closed, e.g. by suturing the incision.

By using the devices and techniques herein, medical procedures andsurgeries can be provided in a safe and efficient manner, at reducedcost and with a reduced risk of damage to a patient's tissue.

Note on Terminology

As used herein, an element or step recited in the singular and proceededwith the word “a” or “an” should be understood as not excluding pluralelements or steps, unless such exclusion is explicitly recited.Furthermore, references to “one embodiment” of the present invention arenot intended to be interpreted as excluding the existence of additionalembodiments that also incorporate the recited features.

While the present invention has been disclosed with reference to certainembodiments, numerous modifications, alterations and changes to thedescribed embodiments are possible without departing from the sphere andscope of the present invention, as defined in the appended claim(s).Accordingly, it is intended that the present invention not be limited tothe described embodiments, but that it has the full scope defined by thelanguage of the following claims, and equivalents thereof.

The invention claimed is:
 1. A soft robotic device comprising: a softrobotic actuator comprising a plurality of accordion extensionsextending outwards in a radial direction, the soft robotic actuatorcapable of being in an inflated state or an uninflated state; and tubingconfigured to provide an inflation fluid to the soft robotic actuator;wherein the soft robotic actuator is sized and configured based on asize and configuration of a target incision or wound, such that in theuninflated state the soft robotic actuator is insertable into the targetincision or wound, and in the inflated state the soft robotic actuatorexerts a force on the periphery of the target incision in the radialdirection to hold the target incision in an open state.
 2. The softrobotic device of claim 1, wherein the soft robotic actuator exerts aforce of about 1 to 3 pounds on the periphery of the incision or woundwhen in the inflated state.
 3. The soft robotic device of claim 1,further comprising an inflation device for supplying the inflation fluidto the soft robotic actuator, wherein the inflation device comprises ahand-operated inflation bulb, catheter balloon inflator, or syringe. 4.The soft robotic device of claim 1, further comprising an inflationdevice for supplying the inflation fluid to the soft robotic actuator,wherein the inflation device comprises one or more pumps, compressors,or regulators for supplying the inflation fluid from a reservoir or anambient environment.
 5. The soft robotic device of claim 4, furthercomprising a control device for controlling the inflation device,wherein the control device comprises a controller programmed to inflateor deflate the soft robotic actuator in response to receiving a controlsignal.
 6. The soft robotic device of claim 1, further comprising asubstantially flat base disposed on a radially inner surface of the softrobotic actuator.
 7. The soft robotic device of claim 1, wherein theinflation fluid comprises at least one of air or saline.
 8. The softrobotic device of claim 1, wherein transitioning the soft roboticactuator from the uninflated state to the inflated state causes the softrobotic actuator to extend in the radial direction and take on a shapeof a partial ellipse.
 9. The soft robotic device of claim 1, wherein thesoft robotic actuator is configured to enter a partially inflated state,and placing the actuator in the partially inflated state varies theamount of force exerted by the soft robotic actuator on the target woundor incision as compared to the inflated state.
 10. The soft roboticdevice of claim 1, further comprising an interface for releasablyconnecting the actuator to the tubing.
 11. A soft robotic devicecomprising: a soft robotic actuator comprising a plurality of accordionextensions extending outwards in a radial direction, the soft roboticactuator capable of being in an inflated state or an uninflated state; ahandle connecting the soft robotic actuator to an inflation device forsupplying an inflation fluid to the soft robotic actuator; and a shaftfor connecting the handle to the soft robotic actuator; wherein the softrobotic actuator is sized and configured to manipulate a body tissue,such that in the uninflated state the soft robotic actuator isinsertable into a target incision, and in the inflated state the softrobotic actuator becomes relatively more rigid to allow the body tissueto be manipulated.
 12. The soft robotic device of claim 11, wherein thesoft robotic actuator exerts a force of about 0.2 to 2 pounds when inthe inflated state.
 13. The soft robotic device of claim 11, furthercomprising the inflation device for supplying the inflation fluid to thesoft robotic actuator, wherein the inflation device comprises ahand-operated inflation bulb.
 14. The soft robotic device of claim 11,further comprising the inflation device for supplying the inflationfluid to the soft robotic actuator, wherein the inflation devicecomprises a foot-operated inflator.
 15. The soft robotic device of claim11, further comprising a control device for controlling the inflationdevice, wherein the control device comprises a controller programmed toinflate or deflate the soft robotic actuator in response to receiving acontrol signal.
 16. The soft robotic device of claim 11, furthercomprising a substantially flat base disposed on a radially innersurface of the soft robotic actuator.
 17. The soft robotic device ofclaim 11, wherein the inflation fluid comprises at least one of air orsaline.
 18. The soft robotic device of claim 11, wherein the softrobotic device provides haptic feedback for controlling an amount offorce exerted by the soft robotic actuator.
 19. The soft robotic deviceof claim 11, further comprising an interface for releasably connectingthe actuator to the shaft.
 20. A soft robotic device comprising: a softrobotic actuator comprising a body and a base, the body of the softrobotic actuator capable of being in an inflated state or an uninflatedstate, the base being substantially flat when the body is in theuninflated state, and that bends and becomes a perimeter of a workingarea formed radially interior to the base when the body is in theinflated state; a handle connecting the soft robotic actuator to aninflation device for supplying an inflation fluid to the soft roboticactuator; and a shaft for connecting the handle to the soft roboticactuator; wherein the soft robotic actuator is sized and configured tomanipulate a body tissue, such that in the uninflated state the softrobotic actuator is insertable into a target incision, and in theinflated state the soft robotic actuator becomes relatively more rigidto allow the body tissue to be manipulated.